1. Field of Invention
The present invention relates to a structure of a roll rod for a vehicle, and more particularly, to a structure of a roll rod for a vehicle which has improved durability and vibration insulation by improving the structure of a rear insulator repeatedly receiving large load.
2. Description of Related Art
A monocoque body that is light and has high productivity is generally used in vehicles, instead of a frame body. A specific frame is removed and a power train including an engine is directly mounted on the car body, in the monocoque body. Therefore, in the monocoque body, the car body itself functions as a frame and a suspension and chassis parts are mounted, but a subframe is mounted at the lower portion of the vehicle in order to prevent vibration of the power train (a mechanism composed of the engine, transmission, and differential gear) from being directly transmitted to the car body and distribute shock in a collision.
The subframe is manufactured in various shapes in accordance with the power and size of the vehicles, while the power train having a high-exhaust and high-torque engine generally uses a subframe having a #-shape composed of four bars arranged in a rectangular.
Further, in a relatively low-exhaust and low-torque engine, as shown in FIG. 1A, a subframe, which is fixed to the car body, has a plate shape where a steering system is mounted, and allows a suspension strut and a knuckle to be connected, is mounted.
Mounting members support at three positions in vehicles equipped with the plate-shaped subframe. That is, an engine mount and a transmission mount are mounted at both sides of the car body and carry the weight of the power train while the roll rod mounted on the subframe controls displacement of the power train and attenuates vibration.
The roll rod is mounted on the subframe by fixing bolts and the detailed configuration is shown in FIG. 1B.
Referring to FIG. 1B, the roll rod includes a fastening rod 10, a mounting member 20, and insulators 50, 60. The fastening rod 10 has a bar shape, in which a rubber bush 13 connected to the transmission is mounted at the end of the portion protruding from the subframe and a sliding portion 11 having a pipe shape is formed at the portion inserted in the subframe. The mounting member 20 fastening the fastening rod 10 to the subframe is fitted on the sliding portion 11. Further, a protrusion 12 is formed at one end of the sliding portion 11 to prevent the mounting member 20 from separating from the sliding portion 11, an end plate 30 is connected to the other end, and a protrusion 21 is formed on the inner circumference of the mounting member. Further, the front insulator 50 and the rear insulator 60 are mounted ahead of and behind the protrusions 21, respectively, on the sliding portion 11. Meanwhile, the end plate 30 is fixed by a bolt 40 passing through the sliding portion 11 and a nut 41 thread-fastened on the bolt 40.
Therefore, the rear insulator 60 is compressed and functions as a damper in accordance with displacement of the power train due to the inertia, when the vehicle moves forward, while the front insulator 50 is compressed and functions as a damper, when the vehicle moves backward or reduces the speed.
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.